This proposal is the second five-year competitive renewal request to continue our ongoing program project studies of DNA structure, dynamics and recognition for the period 1994-98. The solution structure of a variety of biologically important sequences (synthesized in the Core lab) will be studied by chemical probe methods and by high-resolution NRM distance geometry methods. In parallel studies the sequence-dependent dynamics of DNA will be investigated on various timescales via a variety f spectroscopic relaxation techniques, including solid-state NMR, solution-state NMR, EPR (pulsed ELDOR and CW methods) and laser optical (FPA & DLS) methods. Structural measurements using isotopically labelled DNA (synthesized by the Core lab) will also be carried out using solid-state methods (REDOR/DRAMA). The structure of zinc-finger proteins that recognize specific DNA sequences will be determined by high-resolution NMR. Finally, the Core lab will supervise and coordinate the construction of a new 750 MHz NMR spectrometer to increase the sensitivity and resolution of ongoing NMR studies, as well as continuing its role as a DNA synthesis facility by providing normal and isotopically labelled nucleic acid sequences to the participating research groups.